In an evolved packet system (EPS), a basic granularity for quality of service (QoS) control is an EPS bearer. All data flows on a same bearer obtain a same QoS guarantee, and different QoS guarantees need to be provided by different EPS bearers. EPS bearers may be classified into two types according to different QoS: a guaranteed bit rate (GBR) bearer and a non-GBR bearer.
The GBR bearer is mainly used to carry a service such as a voice, a video, or a real-time game using a dedicated bearer. A parameter GBR represents a bit rate that can be expectedly provided by the GBR bearer, and a parameter maximum bit rate (MBR) limits a bit rate that can be provided by the GBR bearer and represents an upper limit of an expected data rate provided by the GBR bearer. The MBR needs to be greater than or equal to the GBR. When resources are strained, traffic that is over the GBR is discarded, but traffic within the GBR needs to be ensured.
The non-GBR bearer is mainly used to carry various data services. The non-GBR bearer may be simply understood as a bearer that provides an Internet Protocol (IP) connection between best effort networks. The non-GBR bearer is set up with setup of a public data network (PDN) connection, and removed with removal of the PDN connection. When a network is congested, a non-GBR service (or bearer) needs to be subjected to a rate reduction requirement.
A backbone network is a network for forming a core connection of the Internet. The backbone network may be a transmit network to which user service data flows from user equipment (UE) through an operator network such as a core network (which may be an EPS network, a circuit switched (CS) network, or the like). A large quantity of data flows converge in the backbone network. Different from QoS control according to a data flow in the EPS network, in the backbone network, a large quantity of resource overheads need to be increased if QoS is controlled according to a granularity of a data flow. Therefore, in an existing network architecture, a backbone network is deployed based on redundancy, and it is considered that network resources are sufficient. The backbone network establishes pipes that meet different QoS and puts, for transmission, data flows with corresponding QoS requirements into the pipes (for example, a GBR pipe and a non-GBR pipe are established).
When the UE is connected to a network, an EPS bearer that meets a subscribed QoS requirement is set up according to user information and service information. When the UE performs a service, a data flow matches, in an EPS system according to IP quintuples of a data flow sender and a data flow receiver, a corresponding EPS bearer for transmission. Data flows flow from the EPS network to the backbone network and then converge in a same pipe for transmission, and are transmitted through the backbone network to a peer end or a corresponding service platform. By means of static configuration in the backbone network, the data flows match, based on IP quintuples of the data flows, an established pipe for transmission. In the foregoing manner, control meeting a QoS requirement in an entire service procedure from the EPS network to the backbone network is implemented.
In a fifth generation (5G) network, as a quantity of terminal users and service volumes increase, control of a software defined networking (SDN)-based architecture on a network poses a higher requirement on network resource utilization. After a large quantity of services converge in the backbone network, congestion may occur. However, in an existing transmission mode, the backbone network does not identify a specific data flow. Consequently, traffic of guaranteed bandwidth of a user cannot be ensured, for example, traffic within a GBR cannot be ensured. As a result, end-to-end QoS of a service cannot be ensured.